Potassium-encapsulated arsenic-dithiolato compounds: Synthesis, structural calculation, and biological relevance

This study based on the synthesis, characterization, and structural calculation of small molecular potassium-encapsulated arsenic-dithiolato compounds will provide fundamental knowledge about arsenic metabolism behavior in biological system. Two novel air-stable potassium-encapsulated arsenic-dithiolato compounds, [K@As2(L1)3](BF4) (1) and [K@As2(L2)3](BF4) (2), were prepared using deprotonated 2,6-bis(mercaptomethyl)pyridine (L1H2) and 1,3-dimercapto-m-xylene (L2H2) to react with AsCl3 in the presence of potassium cation. Compounds 1 and 2 have been characterized by electrospray ionization-mass spectra, nuclear magnetic resonance spectra, and elemental microanalysis. Density functional theory calculation also supports the formation and binding properties of the potassium-encapsulated arsenic-dithiolato compounds.